In the early 1940s, scientists began testing a powerful new insecticide, Dichloro-diphenyl-trichloroethane (commonly called DDT), against gypsy moth. DDT appeared to be a 'magic bullet' against gypsy moths; it killed large populations of the moth quickly and completely. Scientists began to speak of eradicating gypsy moth again. The federal government decided to use DDT on 3 million acres in Michigan, Pennsylvania, and New York as a test to see if eradication of gypsy moth was possible. The areas were sprayed in 1957 but the spraying program was halted after fierce opposition by both the general public and scientists who pointed to the pesticide's devastating overall effect on the environment. Use of DDT was severely limited in the 1960s and completely banned in the United States in the 1970s.